LOS ANGELES -- A California lawmaker wants to make his state the first to ban incandescent lightbulbs as part of California's groundbreaking initiatives to reduce energy use and greenhouse gases blamed for global warming.

The "How Many Legislators Does it Take to Change a Lightbulb Act" would ban incandescent lightbulbs by 2012 in favor of energy-saving compact fluorescent lightbulbs.

"Incandescent lightbulbs were first developed almost 125 years ago, and since that time they have undergone no major modifications," California Assemblyman Lloyd Levine said Tuesday.

"Meanwhile, they remain incredibly inefficient, converting only about 5 percent of the energy they receive into light."

Levine is expected to introduce the legislation this week, his office said.

If passed, it would be another pioneering environmental effort in California, the most populous U.S. state. It became the first state to mandate cuts in greenhouse gas emissions, targeting a 25 percent reduction in emissions by 2020.

Compact fluorescent lightbulbs (CFLs) use about 25 percent of the energy of conventional lightbulbs.

Many CFLs have a spiral shape, which was introduced in 1980. By 2005, about 100 million CFLs were sold in the United States, or about 5 percent of the 2-billion-lightbulb market, according to the U.S. Environmental Protection Agency.

That number could more than double this year. Wal-Mart Stores Inc. alone wants to sell 100 million CFLs at its stores by the end of 2007, the world's biggest retailer said in November.

While it will not give opinion on the possible California law, the EPA recommends CFLs.

"They save money and energy," EPA spokeswoman Enesta Jones said. "They are more convenient than other alternatives and come in different sizes and shapes to fit almost any fixture."

About a fifth of the average U.S. home's electricity costs pays for lighting, which means even if CFLs initially cost more than conventional lightbulbs, consumers will save, Jones said.

A 20-watt CFL gives as much light as a 75-watt conventional bulb, and lasts 13 times longer, according to the Rocky Mountain Institute, a nonprofit group studying energy issues.

Southern California Edison, an Edison International subsidiary and one of the state's biggest utilities, runs a program that cuts the cost of a CFL by $1 to $2.50. In the past year, SCE has helped consumers buy 6 million CFLs, it said.

California Energy Commission member Arthur Rosenfeld said an average home in California will save $40 to $50 per year if CFLs replace all incandescent bulbs.

While not commenting specifically on Levine's likely legislation, Rosenfeld, winner of the Enrico Fermi Presidential Award in 2006, said the switch from incandescent bulbs became feasible about five years ago when CFL performance improved.

"This is clearly an idea whose time has come," he said.

Levine, a Democrat from Van Nuys in Los Angeles, last year introduced a bill that will become law in July that requires most grocery stores to have plastic bag recycling.